The invention relates generally to an improved apparatus regulating air flow between a cooling unit and a compartment in a refrigeration system. In particular, the invention relates to an improved air baffle apparatus.
Conventionally, a refrigeration system provides a single refrigerating or cooling unit in a freezer section of the system for providing cold air to the freezer section. A separate one or more refrigeration compartments is maintained at a cool but not freezing temperature for refrigerating items contained in the compartment. The refrigeration compartment is in fluid communication with the cooling unit, usually through air ducts within the walls of the refrigeration system. A thermostatic control monitors the temperature within the refrigeration compartment controls the opening and closing of an air baffle apparatus within the air duct intermediate the cooling unit and the refrigeration compartment. If the refrigeration compartment becomes warmer than a predetermined temperature, the air baffle apparatus is opened to allow cool air to flow from the cooling unit to the refrigeration compartment; if the refrigeration compartment is sufficiently cool according to predetermined parameters, the air baffle apparatus is closed to preclude air flow from the cooling unit to the refrigeration compartment.
There are occasions when moisture enters the refrigeration compartment, such as when a user opens a door to gain access to the interior of the compartment. Such moisture can collect on an air baffle apparatus and react to the presence of cold air from the cooling unit to form ice. The ice may build up sufficiently to interfere with the operation of the air baffle apparatus, freezing the moving parts of the apparatus and preventing movement of the parts to effect an open or closed orientation to control flow of cold air from the cooling unit to the refrigeration compartment.
Prior art solutions to the problem of ice build-up on moving parts of an air baffle have included provision of spacers intermediate the moving parts to maintain the parts in spaced relation, as disclosed in U.S. Pat. No. 4,903,501 for a "Refrigerator Air Control Heated Baffle" to James O. Harl. A problem with such provision of spacers is that no active motion is available to break up ice formations other than the normal actuation movement of the air baffle apparatus. Thus, if sufficient ice is built up to bridge the gap in the space between the moving parts of the air baffle, only the normal operating movement of the air baffle is available to overcome the binding action of the ice upon the moving parts.
It would be useful to provide an air baffle apparatus for regulating air flow between the cooling unit and a compartment in a refrigeration system which has improved action for breaking ice built up on the air baffle.